Payment will be charged to iTunes Account at confirmation of purchase.

Automatic subscription renewal details: A purchased subscription automatically renews unless auto-renew is turned off at least 24-hours before the end of the current subscription period. You cannot cancel the current subscription during the active subscription period. Your account will be automatically charged for renewal within 24-hours prior to the end of the current period, at the same cost as your current subscription. You can manage your subscriptions and turn off auto-renewal by going into your iTunes Account Settings after purchase.